Gauge block



GGGGGGGGG K.

1,407,833. Patented Feb. 28, 1922.

. -UNITED STATES PATEN T ,OFFICE BRYANT H. BLOOD, OF HARTFORD, CONNECTICUT, ASSIGNOR '1'0 PRATT WHITNEY COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

GAUGE BLOGI.

Speciflcation of Letters Patent. Pateted Feb. 28, 1922..

Application filed June 28, 1919. sera No. 307,459;

To all wit-om it 'may concem:

Be it known that I, BRYANT H. BLOOD, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Gau e Blocks, of which the following is a speci cation. I

This invention relates to gauge blocks provided with opposite parallel flat faces at a predetermined distance apart. 'One Object of the invention is to provide gauge blocks of this type with improved lateral surfaces which are adapted to be easily grasped with.- out slipping and which have an mprovei appearance. Another Object of the invention is to provide an improved configuration at the edges of the bloc to prevent marring of' or interference with the working faces.

In the accompanyin drawng I have shown the preferred em odment of the in Vention, but it will be 'understood that there may be variation, particularly as Concerns the transverse. shape.

Of the drawing:

Fig. 1 is a perspective view.

Fig. 2 is a plan view.

Fig. 3 is an enlarged transverse sectional view taken along the line 3-3 of Fig. 2.

Fi 4 is a view Similar to Fig.`3'but showing the efi`ect of a bruise.

The drawing shows a `gauge block B which is square, but t will be understood that I do not limit myself to this shape and that the blocks may be made circular or otherwise. Each block has opposite parallel plane or fiat end faces 1-1 which are at a predetermined distance apart. The blocks are very accurately constructed as concerns fiatness and parallelism of the surfaces and as concerns the len%'th between them. The lengths are preferab y either multiples or definite fractions, usually decimal fractions, of a predetermined unit of len th. Ordinarily a series of blocks is provi ed of which the several blocks have different lengths so that by combining a number of blocks with their end faces in engagement any desired len h may be built up.

ange blocks of this type are intended for use in machine shops and other places where the hands of the user are apt to be coated with oil. ,In order to prevent the blocks from slippin in the hands of the user and in order furt er to improve the appearance of the blocks, I provide the lateral surfaces 2-2 thereof with a peculiar finish. As somewhat crudely illustrated in Fig. 3, each lateral surface of the block is roughened, being provided with a large number of minute indentations and alternating elevations. In addition to the rou hening of the surface by providing these ndentations and elevations, the surface is further treated to givc it a dull rather than a olished finish. Pre ferably the major roug ening of the block is efi'ected by means of a sand blast process, and the dull finish is subsequently effected by means of a mud blast process. As the result of these two processes used successively, the block is roughened in such a way as to prevent its slipping in the hands of the user, and the roughened or uneven surface is given a dull finish which greatly improves its appearance.

Preferably as illustrated in Fig. 3, the ends of the blocks are slightly beveled, an inclined surface 3 being provided adjacent the main surface 1 at each edge' `thereof. As shown in the ,drawing the included angle between the beveled surface 3 and the end face 1 is a little less than 180 being approximately 172 It will be understood that I do not limit myself to this exact angle but it is essential that the angle be relatively large, preferably being approximately that shown, and certainly not being less than 15O It will be understood therefore that when I refer to slightly beveled surfaces I refer to surfaces at an angle of the order indicated. The corners of the block between the beveled surfaces 3 and the lateral surfaces 2 are rounded as-shown at 4. The beveling of the said surfaces adjacent the edges and the rounding of the corners serve to prevent any minor rotrusions or burrs resulting from an acci ental bruise, from projecting outward in such a way as to interfere with the proper engagement of the block with another Similar block.

Fig. 4 shows a block which has been slightly bruised, with the result that a small protrusion has been raised as shown at 5. It will be seen that on account of the slight beveling of the surface 3 this protrusion does not extend beyond the plane of the main face 1, and thus does not interfere with the proper engagement of the said face 1 with another fiat face. It will be seen that the angle between the surface 3 and the surface 2 is much smaller than-that between the surface 3 and the face 1, the result being that any bruise or protrusion is caused to occur at the smaller angle rather than at the larger one. As shown, a protruson 5 at the smaller angle is larmless whereas the same protrusion at the larger angle would int'erfere with the working face. Clearly if the beveling was such that the two angles were the same the beveling would be of little use as there would be just as much danger of a protrusion at one angle as at the other.

What I Claim is:

1. A gauge block provided with opposite parallel flat end faces and having sand blasted lateral surfaces whereby said surfaces are uniformly roughened, said sand blasted surfaces being mud blasted to give them a dull finish.

2. A gauge block provided with opposite parallel flat end faces and with slightly beveled surfaces at the edges of the end faces, the angle between each beveled surface and the end face bein but a little less than 180 and the ang e between each beveled surface and the corresponding lateral surface being a little more than 90 the said beveled surfaces serving to prevent minor bruises or protrusions at the corners from interfering with the'engagement of the corresponding flat end face with another similar flat face.

3. A gauge block provided with opposite parallel flat end faces and with slightly beveled surfaces at the edges of the end faces and With rounded corners between the BRYANT H. BLOOD. 

